1. Field of the Invention
The present invention relates to a sealing web for bridging expansion joints in structures comprising a stretchable plastic sheet bridging the area of the joint. This plastic sheet is impermeable to moisture, and the marginal sections of this plastic sheet are coated with fiber material solidly secured to the plastic sheet. The marginal sections have at least partly projecting zones of fibers for attaching the plastic sheet to the substrate under it, while leaving uncovered a stretchable center section of the plastic sheet on the top side in the running direction of the sealing web.
2. The Prior Art
Such a sealing web is known from DE 93 17 637 U1. The sealing strip according to this prior art document consists of a plastic sheet web, on which provision is made on both of its sides for an adhesive base for gluing and sealing compounds. The adhesive base is formed by the surface of strips of fleece which have marginal areas that protrude laterally beyond the edge of the web sheet. On their inner sides the strips of fleece are vulcanized into the surface of the web sheet. This is done in such a way that the surface of the web sheet is structured and formed within the zone of its marginal sections by protruding fleece fibers. Good adhesive conditions are available within the area of the adhesive base for gluing the base to a wall covering, for example such as tiles. The elasticity of the web sheet is preserved within the center section.
The drawback with this known sealing web is that the plastic sheet is glued to the ground or substrate under it with the fleece sections serving as an adhesive base like a block of pavement, covering the expansion joint on the top side. Thus, it is possible for fleece strip sections to project beyond the plastic sheet solely for the purpose of securing the plastic sheet onto the substrate. Gluing of the plastic sheet with the sheet resting on the substrate, so as to prevent moisture from penetrating the expansion joint laterally, is not possible with the adhesive intended for gluing the sections of fleece material. The lateral penetration of water seeping into the expansion joint is at best reduced only in that the plastic sheet is marginally pressed onto the substrate by the projecting fleece arranged on the top side. However, as a rule, effective sealing can not be assured due to the roughness of the substrate. In any case, even with such a solution, a hollow marginal space remains, in which water, for example coming from cross joints can circulate in such a hollow space between the fleece material and the plastic sheet, and penetrate into the expansion joint.
The sealing web according to DE 93 17 637 U1 is suitable for application to a wall area. However, the known sealing web is unsuitable for application in the floor area particularly if the floor is subjected to certain types of loads, for example shipping traffic across the floor. The plastic sheet is readily deformable relative to the projecting fleece material which has been hardened by the adhesive. Thus, the plastic sheet represents a substrate that is flexible within certain limits versus other types of zones. Especially with load bearing industrial floors, which, for example, are covered with tiles, and where load bearing traffic takes place on such floors, the tiles in these marginal zones will rest upon a substrate that is yielding to different degrees. This poses the risk that the tiles may break in such transitional zones.
DE-design patent 88 14 650 describes a sealing web intended for area sealing of entire floor sections. However, such a sealing web is unsuitable for bridging expansion joints because they lack elastic properties.